Motor stop or release for electric switches



March as 1924. 1,48 ,443

S. 5. WHEELER MOTOR STOP 0R RELEASE FOR -ELECTRIC SWITCHES Filed Nov. 51920 Fig. 1.

u 3 nu 3 2:3, v 25 3 22 I 3 a?" o P l O O 8 V 1/11 11 1 111/111 IllIII/I 777777. 11

- m S chuyler SX/Vheder, By Attorney Patented Mar. 25, 1924.

PATENT OFFICE.

UNITED STATES SCHUYLER S. WHEELER, BERNARDSVILLE, NEW JERSEY, ASSIGNORTO CROCKER- WHEELER COMPANY, OF AMPERE, NEW JERSEY, A CORPORATION OF NEWJERSEY.

MOTOR STOP OR RELEASE FOR ELECTRIC SWITCHES.

Application filed November 5, 1920. Serial No. 422,093.

To all whom it may concern Be it known that I, SCHUYLER S. Wrmnu ER, acitizen of the United States, residing at Bernardsville, county ofSomerset, and State of New Jersey, have invented certain new and usefulImprovements in Motor Stops or Releases for Electric Switches, of whichthe following is a specification.

Anobject of the invention is to provide a heavy or powerful lockingdevice controlled by a small magnet which, in requiring to be maintainedconstantly by the line, draws only a small amount of current, andgenerates only a small amount of heat.

This being one of the objects of the present invention, other objects ofwhich will appear herein, the invention consists of certain features ofconstruction and combinations of parts to be hereinafter described,

and then claimed with reference to the ac compa-nying drawings,illustrating one embodiment of the invention, in which- Fig. 1 is a planview of the apparatus, partly broken away, and showing the switchlocked;

Fig. 2 is a front elevation thereof, showing the switch locked;

Fig. 3 is a sectional view on the line IIL-III, Fig. 4:, showing partsrelated directly with the. switch; and

. Fig. 4 is a sectional front elevation of parts of the apparatus,showing the posi tion which they assume when the switch is opened.

7 Referring to the drawings, a main-spring 10, like a clock-spring,surrounds and .is

also

fastened to a. shaft 11, which is provided with a handle 12. A bracketor frame 13 is supported upon a slate or other suitable slab 141, andthe other end of the spring is secured to said bracket. A member 15 isfastened to the shaft 11 and carries atone end a hammer 16, and theother end is extended as a tail 16 acting as a resetting part. 7

Hammer 16 constitutes the keeper or armature for the magnet 17, which isin a shunt-circuit 17 a connected across the motor line For alternatingcurrent, the keeper 16 and the magnet 17 are laminated. Knifeswitches18, 19, 20 are connected by a bar 21, which is adapted to be locked incircuit-closing position by means of a lat-ch 22 pivoted at 23 to abracket 24, which is mounted on the slab 14. The operative end of thelatch is provided with an anti-friction roller 25, which engages withthe bar 21 to lock the knife-switches closed. After the switch is closedthe latch 22 will be brought into engagement with the switch-bar 21, andthe switch will be kept closed by the presence of the roller 25 in thepath of the switch-bar. The knife-switches are provided with means, suchas shown, or equivalentmeans, having a tendency to open them, such meansas shown consisting of a suitable pressure spring 26, which is mountedupon the slab 14. Means having a tendency to delicately vhold the latchin either the looking or free position, are fully shown in Fig. 3, andconsist of two pins 27, 27, carrying rollers 28 and located in a recess29 of the latch, in which recess enter a pair of flat springs 30, 31,fixed to the bracket 24:. The free ends of said springs, where theyenter said recess 29, are provided with smallhumps or projections 32, 33adapted to bear upon said rollers 28. When the latch is in lookingposition, in engagement with. the switch-bar 21. the pins 27,27, will belocated to oneside of the humps or projections 32, 33, the latter.bearing upon the said pins and the springs 30, 31, being thus freed oftension. When the latch is moved to open position, the springs 30, 31will first be pressed outwardly and then freed, thus setting the latchto the position shown in Fig. and the pins 27, 27. will be at theopposite sides of the humps 32, 33. Limit pins or stops 34, 35, restrictthe degree of moven'ient of the latch.

The apparatus describedis enclosed in a. box 36, with the exception ofthe operative end of the latch and the handle 12. which is used to latchthe switch. To set the parts for locking the knife-switches 18, 19, 20against their contacts, the operator closes the switches and latchesthem in closed position by rotating the crank-handle 12 until the tailor re-sett-ing means 16 of the hammer 16 raises the latch. The hammer isthen held by the energized magnet 17. It at any time the current in themagnet fails, the hammer 16 will be released and will revolve violentlyabout the shaft- 11, due to actuation by the main-spring 10, and willstrike the latch 22, knocking it to the release position, thus releasingthe knife-switches under the actuation of the retractor spring 26.

The hammer 16 may be designed to strike the latch with any desiredforce, whether it be one pound, ten pounds, or a ton, and yet will beheld by the magnet 17 by a current of any desired degree of fcebleness,such as 1-100 ampere. This is for the reason that when the hammerhead isagainst the magnet 17, it is in such a position that its weight iscounterbalancing the mainspring 10, while at the moment it strikes thelatch 22 its weight is adding to the force of said spring. If the springhas a force say, of one pound, and the hammer head weighs fifteenounces, it will strike with a weight of one pound and fifteen ounces,plus a hammer-blow, depending upon the length of the arc of travel, asdesigned, but it will require to hold it in the other position againstthe magnet only one ounce. The blow of the hammer against the latch isaugmented by the momentum acquired by the hammer in swinging. The forceof the blow is made larger by lengthenin the hammer-arm.

The principle or the apparatus 1s to make the operator, when locking theswitch, store up the desired energy, whatever it ma} be, by turning thehammer crankhandle 12, while the power required by the magnet 17 to holdthe hammer remains very small or negligible. In cases of very heavy blowemploying a heavy hammer, a weight and rope wound on a drum, like in alarge clock, is better than a spring. Also, to use a long spring on thehammer so that it pulls nearly as hard at the moment of striking, and tolatch the switch with a latch which is indifferent to the weight ot theswitch.

The operator is compelled to bring the hammer up to be held by themagnet, and, incidentally, to wind up the main spring by reason oflimiting him to the use of the tail or resetting means 16 of the hammeras the only means he has of setting the latch 22 to hold the switch.

The mechanism described may be used to lock or unlock a valve or othercontrol device instead of a switch.

Obviously, the present invention is susceptible ot' modification, aspars may be omitted. parts added, and parts altered, without changingthe scope of the invention as defined in the claims.

hat I claim as new is:

1. In electrical apparatus of the class described, a holding magnet oflimited power, means for energizing it, a switch. a latch therefor,setting means for said latch, tripping means, comprising a hammer,subject to the holding power of the cncrgized magnet, when said settingmeans has operated on said latch to lock the switch, and, when saidmagnet is dc-energized to release said hammer, permitting the hammer tostrike and trip said latch and allow the switch to open, said settingmeans constituting a tail-extension of said hammer, means for pivotallysupporting said hammer and its setting means, and means for subjectingsaid hammer and setting means to tension when said setting means haslocked the switch.

2. In apparatus of the class described, the combination, with anopenable and closablc control device having means tending to throw itopen, of a balanced latch for said device, having a position such that,when holding said device closed, aforesaid means has no tendency to movethe latch, a power-operated hammer adapted to release said latch fromsaid device, and means of slight force for restraining said hammer.

3.111 apparatus of the class described, a latch, having a. securing anda releasing position, a power-operated hammer, and releasing means inaddition to the weight of the hammer for restraining the action of thehammer upon said latch.

a. In apparatus of the class described, the combination, with anopenable and closable control device having means tending to throw itopen, of a latch for holding the device closed by overcoming the tendcncy of said means, spring means having a tendency to urge said latchinto its holding posit-ion or its releasing position, and to delicatelyrestrain the latch from moving to either of said positions, a powerdevice, latch-disengaging means operable by the power device, and meansindependent of the latch for setting said latch to holding position.

5. In apparatus of the class described, the combination, with anopenable and closable control device having means tending to throw itopen, of a latch for holding the device closed by overcoming thetendency of said means, and having two rollers thereon, and duplexspring means on which said rollers may bear, and having a tendency torestrain said latch from its holding position or its releasing position.

6. In apparatus of the class described, the combination, with anopenable and closable control device having means tendin to throw itopen, of a balanced latch for said device, having a position such that,when holding said device closed, aforesaid mcans has no tendency to movethe latch, a power-o rated hammer adapted to position, a s ring-operatedhammer, and release said late from said device, means means in ad itionto the weight of the of slight force for restraining said hamhammer forovercoming the action of said 1 mer, and means for setting the latch tospring restraining the action of the hammer B holding position. upon thelatch.

7. In apparatus of the class described, a latch, having a securing and areleasing SCHUYLER S. WHEELER.

